A device which records information by using domain wall structures in a magnetic wire has been proposed. Recently, it has been experimentally proven that the position of the domain wall can be changed by applying current to the magnetic wire. Realizing a magnetic memory device using the magnetic wire is expected, but various issues have prevented realization of the device to date. The domain wall is a boundary of the magnetic domains having different magnetization directions.
In the case where uniformity and shape of composition material are ideal, the domain wall in the magnetic wire can easily be moved by applying external magnetic field to the magnetic wire. Thus, some methods are needed to fix the domain wall in an intended position, for using the magnetic wire as the magnetic memory device. In contrast, if the domain wall is fixed securely, an appropriate magnetic memory device can not be fabricated because large current is needed for making the domain wall moved.